Equity - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions |
1 Months Ended | |
---|---|---|
Dec. 15, 2017 |
Jan. 31, 2018 |
|
Equity [Abstract] | ||
Number of shares issued in public offering | 3.2 | 0.3 |
Shares issued, price per share | $ 185.00 | $ 185.00 |
Proceeds from public offering of common stock, net of issuance costs | $ 569.8 | $ 48.7 |